std::atan

 

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abs(int)labsllabsimaxabs (C++11) abs(float)fabs divldivlldivimaxdiv (C++11) fmod	remainder (C++11) remquo (C++11) fma (C++11) fmax (C++11) fmin (C++11) fdim (C++11) nannanfnanl (C++11)(C++11)(C++11)
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fpclassify (C++11) isfinite (C++11) isinf (C++11) isnan (C++11) isnormal (C++11) signbit (C++11)	isgreater (C++11) isgreaterequal (C++11) isless (C++11) islessequal (C++11) islessgreater (C++11) isunordered (C++11)
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HUGE_VALFHUGE_VALHUGE_VALL (C++11)(C++11) INFINITY (C++11) NAN (C++11) math_errhandlingMATH_ERRNOMATH_ERREXCEPT (C++11)	FP_NORMALFP_SUBNORMALFP_ZEROFP_INFINITEFP_NAN (C++11)(C++11)(C++11)(C++11)(C++11)

 

Defined in header <cmath>
float       atan( float arg );
double      atan( double arg );
long double atan( long double arg );
double      atan( Integral arg );		(since C++11)

Computes arc tangent of arg

Parameters

arg

-

value of a floating-point or Integral type

Return value

Arc tangent of arg in radians in the range of [-π/2; π/2] radians.

std::atan(+0) returns +0. std::atan(-0) returns -0

std::atan(+∞) returns +π/2. std::atan(-∞) returns -π/2

See also

atan2	arc tangent, using signs to determine quadrants (function)
asin	computes arc sine (arcsin(x)) (function)
acos	computes arc cosine (arccos(x)) (function)
tan	computes tangent (tan(x)) (function)
atan(std::complex) (C++11)	computes arc tangent of a complex number (arctan(z)) (function template)
atan(std::valarray)	applies the function std::atan to each element of valarray (function template)
C documentation for atan